1. Field of Invention
The present invention relates to scissors and more particularly to a pair of ratchet scissors for smoothly, stepwise cutting a pipe (e.g., water pipe) without causing deformation in a labor saving manner.
2. Related Art
A conventional pair of scissors for cutting pipe (e.g., water pipe) is shown in FIG. 1. The scissors comprises a first assembly 10 including a stationary handle unit 11, a stationary jaw 12 having an inner curved edge, and a shoulder 14; a second assembly 20 including a movable handle unit 21 and a pivotal ring 22 provided at an open end of the handle unit 21; a movable jaw 30 pivotably connected to an intermediate portion of the first assembly 10 and including a blade 31 formed on an inner edge facing the stationary jaw 12, a series of ratchet teeth 32 formed opposite the blade 31, and a raised stop 33 proximate the shoulder 14; a toggle link 40 interconnected a forward portion of the handle unit 21 and a rear portion of the jaw 30; and a pawl 51 pivotably formed between a first pivot joining portion (i.e., joining portion of the link 40 and the handle unit 21) and a second pivot joining portion (i.e., joining portion of the handle unit 21 and the stationary jaw 12), the pawl 51 being engaged with the ratchet tooth 32 and including a spring 51 pivotably formed on the handle unit 21.
A cutting operation of the scissors will be described in detailed below. A user may first place a water pipe in the open jaw in position. Note that a maximum angle between the first and second assemblies 10 and 20 is defined when the stop 33 contacts the shoulder 13. Next, the user may hold the handle with one hand and exert force to move the handle unit 21 toward the handle unit 11. The pawl 51 thus continuously moves from one tooth 32 to the adjacent tooth 32 until the pipe is cut by the blade 31. However, the prior art suffered from a couple of disadvantages. For example, a user is required to exert a great force in the cutting operation. Further, the number of the ratchet teeth 32 is limited (i.e., cutting time is short). Thus, the cut pipe may deform undesirably. Thus, a need for improvement exists.